Field
The present disclosure relates to using a scanner to detect objects located in and entering a confined area, in order to warn of instances when a vehicle or other object will strike or engage the object within the confined area. A specific non-limiting example would be detection of objects in a docking area and detection of a truck entering and backing into the docking area.
Background
This disclosure provides improvements to the techniques described in the independent claims relating to object detection and warning alarms incident to object detection.
In order to avoid accidents in work areas, it is often necessary to provide operators with awareness of objects in the path of vehicles. Similarly, it is desired to make other workers aware of the entry of a vehicle into a workspace. One non-limiting example of such a workspace is a loading dock, in which trucks and other vehicles are often backed into defined confined spaces. While mirrors and video arrangements are used, visibility is limited when backing the vehicle. A backing truck typically has an audible warning and is fairly obvious to people in the area, but a general warning may be ignored in noisy environments. In some cases, people in the area are used to hearing audible warnings from adjacent bays, which sound regardless if there is a danger of collision. There are also cases in which, despite availability of mirrors and video arrangements for the driver, further guidance is desired when backing up.
In some loading dock environments, the distance between a loading door for the building and the dock bumper against which the truck lands is minimal Therefore, if a pedestrian is standing in that area with the loading dock door closed, the pedestrian may be in an unsafe situation and, in a worst case scenario, not be able to get out of the way of the backing truck. It is also desired to warn drivers if a pedestrian is in the dock door area. In addition to collision warning, a warning is desired to warn truck drivers and dock door operators if pedestrians are standing in the dock door area.
One issue with optical scanning devices is to determine the size of the object being scanned. For example if a pedestrian is in a cargo bay, and another pedestrian enters the bay, that is generally not a cause for alarm. If a truck is parked in a loading bay and a pedestrian walks into that bay, it can be presumed that is generally not a cause for alarm and it can be presumed that the pedestrian is aware of the truck.
A different problem is in the detection of multiple objects. Detectors are available that can identify multiple objects, identify their relative distances and track their relative movements. Nevertheless, the presence of a small object in front of a larger object results in blockage of portions of the larger object. The sensed objects can appear as the small object and either a smaller version of the large object consistent with the unblocked portion, or splitting the larger object in two. In the case when the larger object is split into two, it is likely the blockage will reduce the total apparent combined size of the split object.
It is desired to use the techniques or configurations described in the preambles of the independent claims to warn truck drivers and dock door operatives if pedestrians are standing in the dock door area and also if the truck is backing-in. There are several different circumstances involving persons or objects in a loading bay and vehicles using a loading bay; however not all objects involve hazards and not all hazards require the same attention or the same kind of attention.